Abstract 13616: Patient-Prosthesis Mismatch in Bioprosthetic Aortic Valve Replacements as Indicated by the American Society of Echocardiography Guidelines Predicts Long Term Survival
Background: The impact of patient-prosthesis mismatch (PPM) on long term mortality has not been clearly defined, with past studies reaching conflicting results. Historically, long term mortality has ranged from 20-45% among those with severe PPM when measured echocardiographically. In 2009 a new algorithm for calculating PPM was proposed by the American Society of Echocardiography (ASE). Long term mortality in patients with aortic valve replacements (AVRs) who meet criteria for PPM using the ASE guidelines has not been defined.
Methods: Of 723 Edwards Lifesciences bioprosthetic AVRs performed at our institution from Jan 2005 to Dec 2009, 473 (65%) were included in our study that had normal systolic function and had an echo within 1 month of surgery. PPM was considered in patients who met inclusion criteria per ASE guidelines: peak aortic jet velocity > 3 m/s, dimensionless velocity index > 0.25, and acceleration time < 100ms. In qualifying patients, the effective orifice area was calculated echocardiographically and indexed to body surface area (EOAi). Patients were then classified per standard PPM divisions: no mismatch if EOAi ≥ 0.85 cm2/m2, moderate mismatch if EOAi was between 0.84 cm2/m2 and 0.61 cm2/m2, or severe mismatch if EOAi ≤ 0.6 cm2/m2. Long term all-cause mortality was calculated for each of these groups
Results: Prevalence of PPM and mortality data is shown in table 1. Prevalence of moderate and severe PPM was 0.9% and 3.8% respectively. In those with none, moderate, and severe PPM, the number of all-cause deaths was 37 (8%), 0 (0%), and 4 (22%) respectively (P=0.096) over a follow up of 33 ± 17 months.
Conclusion: Algorithmic approach using the current ASE guidelines results in low PPM prevalence in those undergoing Edwards Lifesciences bioprosthetic AVRs. In the few cases of severe PPM, there is a suggestion of increased long term mortality, although not significant in our population.
- © 2011 by American Heart Association, Inc.